For toaster model (https://github.com/opendaylight/controller/blob/f2230bf53bc46a99b50c8ae1ba0de032d4dcfc19/opendaylight/md-sal/samples/toaster/src/main/yang/toaster.yang ) we can see XML payload for RPC restock-toaster as follows:
<?xml version="1.0" encoding="UTF-8"?> <input> <amountOfBreadToStock>0</amountOfBreadToStock> </input>
It is missing namespace, fix it to be:
<input xmlns="http://netconfcentral.org/ns/toaster"> <amountOfBreadToStock>10</amountOfBreadToStock> </input>